1. Chapter 1 Introduction and Data Collection
Business Statistics, A First Course
4th Edition
Chapter 1 Introduction and Data Collection
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

2. Learning Objectives In this chapter you learn:
How statistics is used in business
The sources of data used in business
The types of data used in business
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

3. Basic Concepts of Statistics
Statistics is concerned with:
Processing and analyzing data
Collecting, presenting, and transforming data to assist decision makers
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

4. Key Definitions
A population (universe) is the collection of all members of a group
A sample is a portion of the population selected for analysis
A parameter is a numerical measure that describes a characteristic of a population
A statistic is a numerical measure that describes a characteristic of a sample
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

5. Population vs. Sample Population Sample a b c d b c ef gh i jk l m n
o p q rs t u v w
x y z
b c
g i n
o r u y
Measures used to describe a population are called parameters
Measures computed from sample data are called statistics
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

6. Two Branches of Statistics
Descriptive statistics
Collecting, summarizing, and presenting data
Inferential statistics
Drawing conclusions about a population based only on sample data
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

7. Descriptive Statistics
Collect data
e.g., Survey
Present data
e.g., Tables and graphs
Characterize data
e.g., Sample mean =
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

8. Inferential Statistics
Estimation
e.g., Estimate the population mean weight using the sample mean weight
Hypothesis testing
e.g., Test the claim that the population mean weight is 120 pounds
Drawing conclusions about a population based on sample results.
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

9. Collecting Data Primary Sources Secondary Sources Data Collection
Data Compilation
Print or Electronic
Observation
Survey
Experimentation
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

10. Types of Data Examples: Marital Status Political Party Eye Color
(Defined categories)
Examples:
Number of Children
Defects per hour
(Counted items)
Examples:
Weight
Voltage
(Measured characteristics)
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.

11. Chapter Summary Reviewed basic concepts of statistics:
Population vs. Sample
Parameter vs. Statistic
Primary vs. Secondary data sources
Defined descriptive vs. inferential statistics
Reviewed data types
Categorical vs. Numerical data
Discrete vs. Continuous data
Business Statistics, A First Course (4e) © 2006 Prentice-Hall, Inc.